The present invention constitutes an improvement of my earlier door light unit as set forth in U.S. Pat. No 4,523,408. My earlier door light structure was usable in connection with a sash unit with a window pane mechanism mounted in the outer portion of the outer frame member. This earlier structure is designed for window panes that are relatively large and allow for the relatively complex mechanism as disclosed therein.
Of particular interest is to provide a structure usable as a peephole device for doors. With such a structure, it is possible to view and/or talk to a person standing on the outside of a closed door. Such devices generally preclude a person on the outside to see into the room while the person on the inside is looking outwardly.
Prior art devices designed to provide a peephole capacity are generally relatively difficult to install and do not compensate for any variation in door thicknesses. Such prior art devices are generally disclosed in U.S. Pat. Nos. 1,686,942; 1,732,559; 1,747,156; 1,805,465; 2,489,060; 2,491,758; 2,057,239; 2,508,265; 2,624,922; and 2,638,810.
While some of these prior art structures include a speaking tube along with a viewing port, none of them provide such a functional combination forming an attractive door accessory while being easy to install on doors with varying thicknesses while providing the thermal resistance as a result of the use of molded plastics (polymers).